- 300g Wagyu beef mince
- 100g aged beef fat (see Peter Augustus or any good butcher for this)
- 200g beef chuck coarsely minced
- 2 brown onions finely sliced
- 4 milk brioche burger buns
- 2 tsp white miso
- Heinz tomato sauce to serve
- B&B pickles (you can find these at most supermarkets or specialty grocers)
- 50g kewpie mayo
Place the Wagyu beef mince, aged beef fat and ground beef chuck into large mixing bowl, and work together. Be careful not to overwork, the mix should be just holding together.
Divide the mince into four and gently form into patties about 1.5cm thick, rotating, cupping and patting the meat so it comes together, but doesn’t get too compressed. Make an indentation in the centre of each patty with your thumb (to prevent the patty from forming a dome when it cooks).
Add sliced onions to frying pan on a low heat. Allow onions to cook for 2 minutes then add miso paste and allow to cook down for another 5-8 minutes until browned and translucent. Set these aside.
Season patties on one side to taste and grill/pan fry with the seasoned side down until well browned (2-3 minutes). Turn the patty and top with cheese, grilling until cooked to your liking (3-4 minutes for medium).
Meanwhile, warm the brioche buns in the oven, once toasted spread a light layer of Heinz tomato sauce on the base of the bun and the kewpie mayo on the lid of the bun.
Place B&B pickles on the base of the bun and then follow with the burger patty, top patty with miso caramelised onions, followed by the lid of the bun.
Serve with a plate of fries and American mustard.
Tip: Ask your butcher to mince the steak with a good marbling of fat – 20 per cent fat is a good ratio for juicy burgers.